How to write standard form of the equation circle with a center of (-1,4);circumference 6pie?

1 Answer
Mar 19, 2018

#(x+1)^2+(y-4)^2=9#

Explanation:

#"the equation of a circle in standard form is"#

#color(red)(bar(ul(|color(white)(2/2)color(black)((x-a)^2+(y-b)^2=r^2)color(white)(2/2)|)))#

#"where "(a,b)" are the coordinates of the centre and r is"#
#"the radius"#

#"we have the centre but require to find r"#

#"circumference "=2pir=6pi#

#rArrr=(6pi)/(2pi)=3#

#rArr(x+1)^2+(y-4)^2=9larrcolor(red)"equation of circle"#